Machine for drilling drawing dies



4 v I I 1,629,220 May 17, 1927' s. LQEWENHERZ T MACHINE FOR DRILLINGDRQA'WING DIES Fified Sept.2,\l925 2 Sheets-Sheet 1 May 17,1927.

s. LO EWENHERZ ET AL MACHINE FOR DRILLING DRAWING DIES Filed Sept. 2.1925 2 Sheets-She'et 2 F E" I i m 0 p p p M Patented May 17, 1927'.

UNITED STATES SIIEGM'UND 'LOEWENHERZ AND MAXSTDCKMAYEB, OF BERLIN,GERMANY, ASSIGNORS v'ro PATENT-TREUHAND-GESELZLSCHAFT rim ELEKTRISCHEU'HLAMIPEN 3.11;,

OF EHRENBERGSTRASSE, BERLIN, GERMANY; A CORPORATION'OF GERMANY.

irrAcHInE non DRILLING DRAWING, nms. I

. Application filed Sep-tembe The invention relates to machines forboring drawing discs or dies, in particular diamond dies, in which thereciprocating work holder is retracted mechanically at short in tervalsof time from the rotating drill and is pressed through the medium ofsprings again into contact with the drill. The withdrawal of the workholder is effected in hitherto known machines of this kind usually bymeans of a rocking lever controlled by .a cam bearing against 'a pin orthe like mounted on the work holder and through the medium of the pin orthe like retracting the work holder against the action of the spring. Asthe drill is subjected to continu ous wear and thereby becomes shortenedit has hitherto been necessary in such machines at short intervals oftime to alter the position of the lever acting on the pin attached tothe work holder, so that both the necessary movement of the work holderand the correct time of contact between drill and work are maintainedand the stone is not moved too far after a certain interval of time norkept in contact with the drill.

The invention has forits object to relieve the attendant of thecontinuous inspection of the correct return movement of the work holder.

For this purposein accordance with the invention the work holder'isretracted in a novel manner solely by a' friction or clamping actionefiecfed through the'medium of a pin Or the like adapted to press on thework holder and to reciprocatetherewith. The latterin itsfreturnmovement moves the'work holder with it by friction or clamping effectindependent of its axial position and releases it at the end ofthereturn movement so that it may be pressed forward iii-known manner byspring action and then again returned into initial'position. In thismanner of retracting the work holder even when axial displacement of thesame in relation to the clamping member has taken place due to wear ofthe tool carrier, on the return movement of the work holder it alwaysmoves the same amount since the pin or the like moving the work holderacts exactly the same whether it gripsthe work holder further forward orfurther rearwards in relation to the drill. Preferably a lever rockingabouta fixed pivot and adapted to be displaced is employed forwithdrawing the,work holder 1' 2,-1925. serial No. 54,006.

which lever has a finger-like member adapted to bear on the work holderand receiving from a cam the necessary rocking movement and displacementor rise and falling. move-' ment. In order that the length of stroke may'be varied in accordance with the fineness of the drill point and inorder to be able .to regulate at each stroke the relation of the time"of contact of the -die or stone with the drill to the time necessary forthe withdrawing movement, the'cams acting on the retracting lever arearrangedas double cams on a common axis mounted in the machine franie.

A machine in accordance with the inven-' tion is illustrated in theaccompanying drawing in Figs. 1 and 2 in'plan in difierent positions.tion through the machine on the lineA-B, and Fig. 4, a plan of the mainor driving shaft.

Figs. 5 and 6 show in section to enlarged scale the cams used. a

As shown, on the machine frame a is mounted in a bearing bracket 6 aspindle 01 carrying the drill c which is set in rotation by a beltpulley e. Axially of the drill, 0 is mounted on adjustably mountedrollers f a cylindrical rod 9 to the forward left hand end of which thework or the stone to be drilled is soldered in the usual manner. Therod-like work holder 9 is formed on its upper side with notches i,inwhich engages a blade spring Z secured to an adjustable holder in. Bymeans of the blade spring Z the work holder, which ,is retractedmechanically at predetermined short intervals, of time, is alwaysagainpressed forward towards the drill 0. The work holder 9 is retracted by afinger-like pressure member or acam m adapted to press on the workholder, which cam is mounted on the upper end ofa lever n, which isunder the action of a spring 0 tending to press it and the cam m againstthe work holder g. By means of a sets crew m extending through a slot-min the cam, the cam m can be finely adjusted vertically and on any wearof its surface taking; place can be re-adjusted The upright lever nwhich carries the cam is adaptedto-be rocked about a slot m on a fixedhorizontal pivot nland is adapted to be displacedin'its longitudinaldirection, so that the cam m may be moved rectilincarly and Fig. 3, is atransverse secii. i i '1 mounted on an eccentric p on shaft 8 which isrotated continuously from a belt pulley The one camdrive consists of acam loring p, which is adjustable by rotation on about the pivot n thecam p keyed to the shaft 8 and is adapted to be clamped by a screw 12'at: suitable relative positions. A project-on n on the lever'n ispressed continuously against the armed lever u is raised. This lever inits upward movement presses against the set thereby moved out ofcontactwith the work holder which then is moved towards the drill 0 b itagain. ears on the drill. On further partial revolution of the shaft sthe camp again moves into position shown in Fig. 1. As the projection non the lever n due to the action of the spring 6 is continuously pressedinto contact with the cam ring p and thus is moved again towards theright,

periphery of the cam ring 1) by a spring' on this partial revolution ofthe shaft 8 and so that ,on each revolution of the double cam p. 7). thelever n is'rocked to and fro On two similar cam discs 9. g. off-set inrelation to one another, rests a single armed lever u adapted to rockabout the pivot u, a spring a pressing the lever into contact with bothcams g. (1..

. Above this lever u which on each rotation lever n falls by gravity,being however assisted in its downward movement by the p g until the camm again comes into cam discs 9. q. the one-armed lever u hears mecontact with the work holder and is pressed against it by the action ofthe spring 0.

' When the machine is to be used the shaft 8 is first preferably rotatedby hand until the pair of eccentrics p. p. and g. g. and the lever 01.assume the positions shown in Fig. 1. and the cam m is out of contactwith the work holder 9. Then by inserting the blade spring I in a notchin the work holder 9, the stone or die is pressed against the drill candthereupon both the drill and the shaft 8 are set in rotation.

After apart of a revolution of the shaft 8 and of the cam discs I g.secured thereto, the lever u moves downward and therewith the lever 11.and the cam m as shown in Fig. 2. The cam is thus pressed firmly by thespring 0 against the work holder 9. After a further portion of arevolution of the shaft .9, the outer cam ring p comes into action andpresses the lower end a of the lever n to the left as' shown dotted inFig. 2., against the action of the spring t. The upper end of the lever11 rocking about a pivot 11. thus moves 'to the right, the cam m tak--ingthe work holder 9 with it in the direction indicatedv by the arrow.As soon as this movement has occurred the two cam discs 9. q. havealready rotated so far by the rotation of the shaft 8 that the single ofthe cam p the upper end of the lever 11.

the blade spring I until the stone with the cam m, moved away from thework holder, moves to the left and thus returns, without movin the workholder, into the initial position s own in 'Fig. ,1., whereupon on thenext rotation of the shaft 8 the upward and downward movement describedand the rocking movement of the lever n are again repeated. The cam mthus continuously moves and takes the work holder 9 with it through thesame distance whether or not due to wear of the drill its axial positionin relation to the cam has altered. Only the zone of movement isdisplaced.

Of the two cam discs g. g. acting on the single-armed lever the one '9is preferably keyed to the shaft 8 while the other g is 1'0- tata'blyadjustable by means of the screw 9 According to the relative position ofthese against different cam portions of the .cam discs 9. g. for alonger or shorter period. The time during which the cam m israised clearof the work holder and the time diiring which it remains in contacttherewith and the time during which the stone and drill are in contactcan-thusbe adjusted within wide limits. To facilitate this adjustmentamark is provided on an annular extension 9 of the cam disc 9 which canbe moved in relation to a scale provided on 1 the fixed collar 8' on theshaft 8. In similar manner the cam ring 2 rotatable on the fixed cam p"and adapted to be clamped by means of a. screw 1; has an annularextension 12 provided with a mark which is adjustable in relation to ascale providedgon the fixed' collar 8 The collar 8 may,-as shown, be inone with the fixed inner cam but maybe separately mounted on the shaft8. Accordin to the adjustment effected by rotation of t e cam 10 on thefixed cam p a smaller or larger totaleccentricity of the double cam androcking movement of the lever'n and thus a smaller or larger stroke ofthe work holder 9 can be obtained. Movement of the work holder can thusbe adjusted to any fineness of the. drill point.

If the 'work holder is to be moved out of action, for example, in orderto allow of .sharpening or exchanging the drill the onearmed lever u' israised by rotation of a lever :1: provided on'the cam w into theposition shown dotted inIFig. 1. in which this lever andalso the lever nwith the cam m 1 thereby raised are no longer operable by the cam discsas'well press from one slde or from be neath against the work holder. Itmay,

moreover, have various shapes and various kinds of movement. "By takingthe movement of the cam m from cams which are mounted on a shaft itselfmounted in the machine, a very simple construction is obtaineda'veryparticular advantage of the new machme.

y dispensing wlththe gearing otherwise -located externally of themachine for moving thework holder, moreover, the inspection of themachine is simplified.

We claim: c A

1. A machine for drilling drawing dies, in particular diamond dies,including a drill, a work holder adapted to be reciprocated in relationto the drill, and means for moving the work holder through the samedistance independently of its position during the drilling operation,said means including a pressure applying'member adapted to press onand'displace said work holder.

7 2. A machine for boring drawing dies in particular diamond dies,including a drill, a work holder adapted to; be reciprocated in relationto the drill and means. for moving the work holder independently of itsposition and zone of movementf s aid means including arockinglever and'apressure applying member adjustably secured to said rocking lever andadapted to be'displaced with said lever and to press on and displace thework holder. i

3. A machine for drilling drawing dies, in particular diamond dies,including a drill,

a work holder adapted to bereciprocated in,

relation to the drill, means for moving the workholder through adefinite distance independently of its position. said means including arocking leverand, .a pressure applying member adapted'to be displacedwith said lever and to press on and displace the work holder, and camsactuating said presllsure applying member and said rocking ever. I

4. A machine for drilling drawing dies, in particular diamond dies,including a drill, a work holder adapted to be reciprocated in relationto the drill and means for moving the work holder independently of itsposi tion, said means including a rocking lever and a pressure. applyingmember adapted to be displaced with said lever and to press on anddisplace the work holder, and camsactuating said pressure member andsaid rocking, lever, said cams adapted to be displaced in relation toeach other, substantially as and for the purpose set forth.

5. A machine for drilllng drawing dies, in particulardiamond dies,including a drill, a work holder adapted to be reciprocated inrelation'te the drill, and means for moving the work holder through adefinite distance independently of its position, said means in-' eludinga rocking lever and a pressure applying member adapted to'be displacedwith said lever and to press on and displace sa'd work holder, a drivingshaft and cams coiltrolling said pressure member and said rocking lever,said cams movably mounted on said driving shaft.

6. A machinefor drilling drawing dies, in particular diamond dies,lncludin a drill, a work holder adapted to be reclprocated in relationto the drill, and means for mov- I ing the work holder through adefinite distanceindependently of its positi on, said means including arocking lever and a pressure applying member, adapted to be' displacedwith said lever and to press on and displace the work holder, a drivingshaft and cams controllingsaid pressure member and said rocking lever.

7. A machine for drilling drawing dies, in particular diamond dies,including a drill, a work holder ada ted to be. reciprocated in relationto the dri l and means for moving the work holder through a definitedistance independently of its position said means including a rockinglever and "a pressure applying member adapted to be displaced with saidlever and to press on the work holder, a driving shaft and earnscontrolling said pressure member and said'rocking lever, said camsmovably mounted on .said driving shaft and ineans for rendering saidcams 1n- .efi'ective on said rocking lever and pressure member. s p 8. Amachine for drill ng drawing dies particularly'" 'diamond diesi",comprising a drill, 'a spring-urged-work holder reciprocable withrespect thereto-and'means frictionally engagingthe workholder -toretract the work holder againstspring action from the drilla definiteamount independent of the fed position of the holderdurin-g the.drilling and the depth of hole.

9. A machine for drilling drawing dies particularly diamond". dies,comprising a drill, a spring-urged work holder reciprocable wlth respectthereto, means to frictionallygrip said holder after each feed movementand means to actuate the gripv ping, means in substantially rectangulardirections. d

' 10. A machine for drilling drawing dies particularly diamond dies,comprising a drill, an alined spring-urge work holder therefor, pivoted.retracting means engaging the holder and means to cause the pivotedmeans to move on its pivot with its point of engagement with the holdermoving in a straight line the same distance independent of the fedposition of the holder.

11. A machine for drilling dies particularly diamond dies, comprising adrill, an

alined, spring-urged work holder therefor,- a pivoted lever to retractthe holder a definite distance, and cams controlling the movement ofsaid lever, the cams of a pair being relatively adjustable to vary theirtiming.

12. A machine for drilling dies, particularly diamond dies comprising adrill, an

the lever to disengage said device'and per mit the holder to feed.

alined spring-urged work holder thereifo j pivoted spring-urged lever, aspring-urge d I grippin member on said lever to engage i In testimonythat we claim the foregoing;

as our invention, we have signed our names,

SIEGMUND LOEWENHERZ. MAXSTOCKMAYER.

